<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .clearfix:after{
            content: "";
            display: block;
            clear: both;
        }
        .content{
            min-width: 600px;
            padding: 0 200px;
            background-color: #ccc;
        }
        .center{
            width: 100%;
            
            height: 800px;
            background-color: #aaa;
            float: left;
        }
        .left{
            width: 200px;
            height: 800px;
            margin-left: -100%;
            background-color: #acf;
            float: left;
            position: relative;
            left: -200px;
        }
        .right{
            width: 200px;
            height: 800px;
            margin-left: -200px;
            background-color: #acf;
            float: left;
            position: relative;
            right: -200px;
        }
    </style>
</head>
<body>
    <div class="content clearfix">
        <div class="center"></div>
        <div class="left"></div>
        <div class="right"></div>
    </div>
</body>
</html>